Aquatic Tower

Aquatic creature spells you cast cost
{u}{u} less to cast. This effect reduces
only the amount of colored mana you
pay. (Aquatic creatures are Krakens,
Serpents, Leviathans, Octopuses, Merfolk,
Squid, Fish, Whales, Sharks, Sponges, Crabs,
Homarids, and Starfish.)